Helleborus plant named ‘RD09’

ABSTRACT

A new and distinct cultivar of  Helleborus  plant named ‘RD09’, characterized by its upright and mounding plant habit; variegated developing leaves; uniform, continuous and freely flowering habit; dark purple-colored flowers held above the foliar plane on relatively long peduncles; and good garden performance.

Botanical designation: Helleborus×hybridus.

Cultivar denomination: ‘RD09’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Helleborus plant, botanically known as Helleborus×hybridus and hereinafter referred to by the name ‘RD09’.

The new Helleborus plant is a product of a planned breeding program conducted by the Inventors in Devon, United Kingdom. The objective of the breeding program was to create new freely-flowering Helleborus plants with strong peduncles that hold attractive flowers above the foliar plane.

The new Helleborus plant originated from a cross-pollination conducted by the Inventors in Devon, United Kingdom in January, 2009 of a proprietary seedling selection of Helleborus×hybridus identified as code designation EXC14562, as the female, or seed, parent, not patented, with a proprietary seedling selection of Helleborus×hybridus identified as code designation OR12054, as the male, or pollen, parent, not patented. The new Helleborus plant was discovered and selected by the Inventors as a single flowering plant from within the progeny of the stated cross-pollination grown in a controlled greenhouse environment in Devon, United Kingdom in February, 2011.

Asexual reproduction of the new Helleborus plant by tissue culture in a controlled greenhouse environments in Roelofarendsveen, The Netherlands since March, 2011, has shown that the unique features of this new Helleborus plant are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the new Helleborus have not been observed under all possible combinations of environmental conditions and cultural practices. The phenotype of the new Helleborus plant may vary somewhat with variations in environmental conditions such as temperature and light intensity without, however, any variance in genotype of the new Helleborus plant.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘RD09’. These characteristics in combination distinguish ‘RD09’ as a new and distinct Helleborus plant:

-   -   1. Upright and mounding plant habit.     -   2. Variegated developing leaves.     -   3. Uniform, continuous and freely flowering habit.     -   4. Dark purple-colored flowers held above the foliar plane on         relatively long peduncles.     -   5. Good garden performance.

Plants of the new Helleborus differ from plants of the female parent selection in the following characteristics:

-   -   1. Plants of the new Helleborus are taller than plants of the         female parent selection.     -   2. Plants of the new Helleborus and the female parent selection         differ in flower color as plants of the female parent selection         have whitish green-colored flowers.

Plants of the new Helleborus differ from plants of the male parent selection in the following characteristics:

-   -   1. Plants of the new Helleborus are shorter than plants of the         male parent selection.     -   2. Plants of the new Helleborus and the male parent selection         differ in flower color as plants of the male parent selection         have dark pink-colored flowers.

Plants of the new Helleborus can be compared to plants of Helleborus×hybridus ‘ABCRD01’, disclosed in U.S. Plant Pat. No. 24,149. In side-by-side comparisons conducted in Devon, United Kingdom, plants of the new Helleborus differed from plants of ‘ABCRD01’ in the following characteristics:

-   -   1. Plants of the new Helleborus were taller than plants of         ‘ABCRD01’.     -   2. Plants of the new Helleborus had longer leaves than plants of         ‘ABCRD01’.     -   3. Plants of the new Helleborus had variegated developing leaves         whereas plants of ‘ABCRD01’ had solid green-colored developing         leaves.     -   4. Plants of the new Helleborus had larger flowers and larger         inflorescences than plants of ‘ABCRD01’.     -   5. Plants of the new Helleborus and ‘ABCRD01’ differed in flower         color as plants of ‘ABCRD01’ had red purple-colored flowers.     -   6. Plants of the new Helleborus had longer peduncles and         pedicels than plants of ‘ABCRD01’.

BRIEF DESCRIPTION OF THE PHOTOGRAPH

The accompanying colored photograph illustrates the overall appearance of the new Helleborus plant showing the colors as true as it is reasonably possible to obtain in colored reproductions of this type. Colors in the photograph may differ slightly from the color values cited in the detailed botanical description which accurately describe the colors of the new Helleborus plant.

The photograph comprises a close-up view of a typical flowering plant of ‘RD09’.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photograph and following observations, measurements and values describe plants grown during the winter in three-liter containers in an outdoor nursery in Boijl, The Netherlands and under cultural practices typical of commercial Helleborus production. During the production of the plants, day temperatures ranged from 0° C. to 10° C. and night temperatures ranged from −15° C. to 0° C. Plants were one year old when the photograph and the description were taken. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 2001 Edition, except where general terms of ordinary dictionary significance are used.

-   Botanical classification: Helleborus hybridus ‘RD09’. -   Parentage:     -   -   Female, or seed, parent.—Proprietary seedling selection of             Helleborus×hybridus identified as code designation EXC14562,             not patented.         -   Male, or pollen, parent.—Proprietary seedling selection of             Helleborus×hybridus identified as code designation OR12054,             not patented. -   Propagation:     -   -   Type.—By tissue culture.         -   Time to initiate roots, summer.—About 15 days at             temperatures about 22° C. to 25° C.         -   Time to produce a rooted young plant, summer.—About two             months at temperatures about 20° C.         -   Root description.—Fleshy, vigorous; white to brown in color. -   Plant description:     -   -   Plant and growth habit.—Herbaceous perennial; upright and             mounding plant habit with flowers held above the foliar             plane; moderately vigorous to vigorous growth habit.         -   Plant height.—About 30 cm to 40 cm.         -   Plant diameter (area of spread).—About 25 cm to 30 cm. -   Leaf description:     -   -   Arrangement.—Leaves arranged alternately in a basal rosette;             leaves palmately compound with three to five leaflets per             leaf.         -   Leaflet length.—About 10 cm to 15 cm.         -   Leaflet width.—About 5 cm to 8 cm.         -   Leaflet shape.—Palmate; elliptic to ovate.         -   Leaflet apex.—Acute.         -   Leaflet base.—Cordate to acute.         -   Leaflet margin.—Dentate to serrate.         -   Leaflet texture, upper and lower surfaces.—Smooth, glabrous;             leathery.         -   Leaflet venation pattern.—Pinnate.         -   Leaflet color.—Developing leaves, upper surface: Close to             139A; central spots, close to 191B; center becoming closer             to N187C with development. Developing leaves, lower surface:             Close to 138A slightly overlain with close to N187A. Fully             expanded leaves, upper surface: Close to 139A; venation,             close to 139C, distally, close to 187A. Fully expanded             leaves, lower surface: Close to 138A; venation, close to             139B, distally, close to N199A.         -   Petioles.—Length: About 12 cm to 18 cm. Diameter: About 4 mm             to 8 mm. Texture, upper and lower surfaces: Smooth,             glabrous. Color, developing leaves, upper and lower             surfaces: Close to 138A; spots, close to 187A. Color, fully             expanded leaves, upper and lower surfaces: Close to 138A;             spots, close to N199A. -   Flower description:     -   -   Flower shape and habit.—Single-type rotate flowers arranged             in loosely branched cymes; freely flowering habit with             typically about eight to twelve flowers developing per cyme             and up to 40 flowers developing per cyme in the second year             of growth; flowers facing outwardly.         -   Fragrance.—None detected.         -   Natural flowering season.—Plants begin flowering about two             months after planting; plants flower from January until             March in the United Kingdom.         -   Flower longevity on the plant.—About two months; flowers             persistent.         -   Inflorescence height.—About 30 cm to 40 cm.         -   Inflorescence diameter.—About 30 cm to 40 cm.         -   Flower buds.—Length: About 2 cm to 3 cm. Diameter: About 1             cm to 2 cm. Shape: Elliptic to ovate. Color: Close to N77A.         -   Flower diameter.—About 7 cm.         -   Flower depth (height).—About 2 cm to 4 cm.         -   Petals.—None observed; transformed into nectaries.         -   Sepals.—Quantity and arrangement: Five arranged in a single             whorl. Length: About 4 cm. Width: About 3 cm to 4 cm. Shape:             Elliptic to obovate. Apex: Rounded to obtuse. Base: Rounded             to obtuse. Margin: Entire. Texture, upper and lower             surfaces: Smooth, glabrous. Color: When opening and fully             opened, upper surface: Close to N77C. When opening and fully             opened, lower surface: Close to N77A to N77C.         -   Peduncles.—Length: About 20 cm to 25 cm. Diameter: About 5             mm to 10 mm. Strength: Strong. Aspect: Mostly upright.             Texture: Smooth, glabrous. Color: Close to 138A; spots,             close to 187A.         -   Pedicels.—Length: About 5 cm to 7 cm. Diameter: About 3 mm             to 4 mm. Aspect: About 10° from peduncle axis. Strength:             Strong. Texture: Smooth, glabrous. Color: Close to 138A;             spots, close to 187A.         -   Reproductive organs.—Stamens: Quantity per flower: About 40             to 60. Filament length: About 1.5 cm to 1.8 cm. Filament             color: Close to 4D. Anther shape: Elliptic to ovate. Anther             length: About 2 mm. Anther color: Close to 4A. Pollen             amount: Scarce. Pollen color: Close to 4A. Pistils: Quantity             per flower: About five. Pistil length: About 2.5 cm. Stigma             shape: Club-shaped. Stigma color: Close to 4B. Style length:             About 1.5 cm. Style color: Close to 183A. Ovary color: Close             to 183A.         -   Nectaries.—Quantity per flower: About 10 to 14. Length:             About 5 mm to 7 mm. Width: About 2 mm to 5 mm. Shape:             Funnelform. Color: Close to N144C; towards the apex, close             to 149B.         -   Seeds and fruits.—Seed and fruit development have not been             observed on plants of the new Helleborus. -   Garden performance: Plants of the new Helleborus have been observed     to have good garden performance and to tolerate rain, wind and     temperatures ranging from about −10° C. to about 35° C. -   Pathogen & pest resistance: Plants of the new Helleborus have not     been observed to be resistant to pathogens and pests common to     Helleborus plants. 

It is claimed:
 1. A new and distinct Helleborus plant named ‘RD09’ as illustrated and described. 